Vehicular hazard warning system

ABSTRACT

An apparatus and method warn drivers of a hazardous condition experienced by another driver. The apparatus generally includes a warning indicator, such as for example a strobe light, coupled to a vehicle warning controller. The vehicle warning controller is connected between a power source and a plurality of vehicle detecting circuits which detect the activation of a safety device. Vehicle detecting circuits can include an antilock braking system (ABS) detecting circuit, an airbag deployment detecting circuit, a rollover protection detecting circuit and an obstacle detector detecting circuit. When at least one of the vehicle&#39;s detecting circuits detects the activation of a safety device due to a hazardous condition, a signal is sent to the vehicle warning controller. The warning indicator is activated in response to a signal from the vehicle&#39;s warning controller. Therefore, driver intervention is alleviated in warning other motorists of potential danger.

FIELD OF THE INVENTION

The present invention relates to the field of motor vehicles. Moreparticularly, the present invention is directed to a system thatprovides a warning to others of the possibility of a hazard experiencedby a driver of a vehicle in which the warning system is installed.

BACKGROUND

Prior art vehicular warning light systems commonly include a taillightassembly, headlight assembly, brake light assembly, turn signalassembly, and an emergency flasher assembly, all employing incandescentlight bulbs. Each of these assemblies operates in a well-known manner toilluminate the roadway, to indicate an impending stop or slowdown,indicate an impending turn, or indicate an emergency condition of somenature.

Conventional vehicular warning lighting systems suffer from certaindrawbacks under modern driving conditions. For example, emergencyflashers, which are standard equipment on motor vehicles, require that avehicle occupant operate the flashers by pressing a switch that isusually located on or near a vehicle's steering column. Typically, theseflashers are employed by the driver when the driver is in a distressfulsituation or to warn others including other drivers, of the vehicle'spresence. Therefore, if the driver or other occupant cannot activate theflashers, other drivers will not become aware of a driver's peril or thevehicle's presence.

Another conventional vehicular warning lighting system is the use ofbrake lights. The driver must apply the brakes in order to activate thiswarning device to alert others of a potential hazard. Even if the driverdoes activate the system, occasions can arise where there is stillinsufficient warning to others. For example, in the situation where aleading vehicle applies a conventional brake light system used toindicate that the vehicle is slowing down or stopping, a followingvehicle may not have sufficient time to stop because the followingvehicle may be located too close to the leading vehicle such that thebrake lights of the leading vehicle cannot be seen in sufficient time toallow the following vehicle to stop. Additionally, on very sunny days,the intensity of the brake lights is such that a driver may not be ableto determine whether the brakes have been applied in the leadingvehicle.

Other forms of vehicular warning systems include horns, flares or awhite flag or towel displayed on the vehicle to indicate that the driveris in distress. In each of these cases, however, these warning systemsrequire driver intervention.

Therefore, it can be appreciated that there exists a need for avehicular warning system which indicates to others that a vehicle or itsoccupants are experiencing a hazardous condition or are in a dangerousposition, but which does not require any intervention from the driver ofthat vehicle.

SUMMARY OF THE INVENTION

In view of the foregoing disadvantages inherent in known types of priorart vehicular warning systems, the present invention provides avehicular warning system, which detects when the automobile in which itis employed has engaged a safety mechanism or is in a hazardouscondition and provides an appropriate warning to others about thecondition.

To attain this, the vehicular warning system of the present inventiongenerally comprises at least one warning indicator which is detectableoutside of the car in which the system is installed, such as a light oran audible indictor which is operationally coupled to a warningcontroller. Examples of a light indicator include a strobe light, orother high intensity light. The audible indicator could be a horn. Thewarning controller, which is preferably a microprocessor, isoperationally coupled to a power source and a detecting circuit(s) whichdetects the activation of a vehicle safety device or detects a hazardouscondition with regard to the vehicle in which the warning system isinstalled. Examples of hazardous conditions include the vehicle reachingits maximum braking capacity and the wheels locking up, the vehicleexperiencing frontal or side impact, the vehicle positioned too close toan obstacle such as another vehicle, a pedestrian, etc., the vehicletilting over and other similar situations. Examples of detectingcircuits include an antilock braking system (ABS) detecting circuit, anairbag deployment detecting circuit, a rollover protection detectingcircuit and a parking aid detecting circuit. Upon activation of at leastone of the abovementioned vehicle safety devices, a signal from anassociated detecting circuit(s) is provided to the vehicle warningcontroller. The vehicular warning system is activated in response to asignal or signals from the vehicle warning controller. Upon detection ofthe signal, the warning indicator is automatically engaged so that thereis no need for driver intervention.

It is to be understood that the invention is not limited in itsapplication to the details of construction and arrangements of thecomponents set forth in the following description or illustrated in thedrawings. The invention is capable of other embodiments and of beingpracticed and carried out in various ways. Also, it is to be understoodthat the phraseology and terminology employed herein are for the purposeof description and should not be regarded as limiting.

The term "vehicle" as used herein includes, but is not limited to, alltypes of motorized transportation including automobiles, trucks, vans,motorcycles and the like. The term "automatically" is used herein tomean that the system is activated without human intervention.

As such, those skilled in the art will appreciate that the invention,upon which this disclosure is based, may readily be utilized as a basisto design other structures, methods and systems for carrying out thepurpose of the present invention. It is important, therefore, that theclaims are regarded as including such equivalent construction insofar asthey do not depart from the spirit and scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood when consideration is given tothe following detailed description thereof. Such description makesreference to the annexed drawings wherein similar reference charactersrefer to similar parts throughout the several views of the drawings:

FIG. 1 is a block diagram depicting the functional interrelationships ofthe components of the vehicular warning system of the present invention.

FIG. 2 is a block diagram depicting the functional interrelationships ofthe components of an airbag system and the vehicular warning system ofthe present invention.

FIG. 3 is a block diagram depicting the functional interrelationships ofthe components of a rollover protection system and the vehicular warningsystem of the present invention.

FIG. 4 is a block diagram depicting the functional interrelationships ofthe components of an obstacle detection system and the vehicular warningsystem of the present invention.

FIG. 5 is a block diagram depicting the functional interrelationships ofthe components of an antilock braking system (ABS) and the vehicularwarning system of the present invention.

DETAILED DESCRIPTION

The present invention is a vehicle warning system for alerting driversthat the vehicle containing the vehicle warning system is experiencingdangerous or potentially dangerous conditions or is in a hazardousposition. The vehicle warning system of this invention preferablyincludes at least one detecting circuit to detect activation of at leastone safety device within the vehicle or to detect a hazardous roadcondition. In the alternative and as shown if FIG. 1 a plurality ofdetecting circuits may be used, each connected to an electronic controlunit (ECU) of a vehicular safety device. According to one aspect of thepresent invention, each of the detecting circuits may be usedindependently of one another. The detecting circuits which may beemployed with the present invention include an (ABS) activationdetecting circuit, an airbag deployment detecting circuit, a rolloverprotection system activation detecting circuit and an obstacle detectiondetecting circuit, although it will be appreciated that the vehicularwarning system of the present invention may be used in conjunction withany vehicle safety device concurrently installed in the vehicle.Referring to FIG. 1, each of the detecting circuits (5-8) is connectedbetween an ECU for each of the safety devices and a vehicle warningcontroller 100. In particular, detecting circuit 5 is connected betweenairbag system ECU 10 and warning controller 100. Detecting circuit 6 isconnected between rollover protection system ECU 20 and warningcontroller 100. Detecting circuit 7 is connected between obstacledetection system ECU 30 and warning controller 100. Detecting circuit 8is connected between ABS system 40 and warning controller 100. Each ofthe above-mentioned detecting circuits receives a signal from itsrespective ECU, indicating the activation of the corresponding safetydevice. Various signaling methods can be employed to communicate to thedetecting circuits that a safety device has been triggered. Such asignaling method may include the generation of an electrical or opticalpulse by the ECU such that the detecting circuit is notified when asafety device has been activated. While the respective detectingcircuits have been illustrated as discrete elements, they could,alternatively, be provided in an integrated design.

The output of each of the detecting circuits is provided to a vehiclewarning controller 100 which in turn is functionally connected to apower supply 101 and a warning indicator 200. Alternatively, a pluralityof warning controllers 100 may be employed. Warning indicator 200 mayinclude, for example, a light such as a high-intensity light or a horn,or a combination of such devices. Electrical power is provided by aconventional storage battery, solar battery or other power source 101supplemented as necessary by a conventional electrical generating system(not shown). Each of the detecting circuits continuously monitors itsrespective ECU and emits an alarm signal to the warning controller 100when its respective ECU indicates that a safety device has beenactivated. Warning controller 100 then activates warning indicator 200which transmits a warning signal that a hazardous condition has beendetected. The warning signal can remain activated until a predeterminedtime has expired. Alternatively, the warning signal can be terminatedautomatically or manually by the vehicle occupant.

According to FIG. 1 and the principles of the present invention,hazardous conditions are detected (acknowledged) by sensors (1-4).Sensors (1-4) may include, but are not limited to, short-circuiting ringsensors, ultrasonic sensors, solenoid plunger sensors, optical sensors,etc. Sensors (1-4) represent a peripheral communications link between avehicle and the ECU used for processing. Sensors (1-4) convert physicalquantities such as the external force applied to the body of a vehicleinto an electrical quantity adapted to communicate with a processingdevice such as an ECU. Examples of such sensors include, but are notlimited to, fiberoptic sensors, inductive sensors, gradient sensors,tangential senors, radar sensors, piezoelectric sensors, and the like.

The entire device as shown in FIG. 1 may be mounted within a smallcabinet and secured beneath the dashboard of an existing vehicle.Alternatively, the present invention may be incorporated as originalequipment in an automobile or other types of vehicle and may be mountedin any convenient location therein.

The following is a description of the various implementations of thevehicular warning system used with the systems of the present invention.

System For Detecting Airbag System Deployment

An airbag system is a vehicular occupant protective system designed toprotect a vehicular occupant in case of a vehicle collision. An airbagsystem generally includes a sensor for detecting a vehicle collision, aninflator for releasing gas into an airbag when a signal is received fromthe sensor and an airbag that inflates with gas released from theinflator. When a vehicle experiences a collision, the airbag inflatesbetween the vehicular occupant and interior components of the vehicle,such as a dashboard or a steering wheel located in front of thevehicular occupant.

FIG. 2 illustrates an airbag system which may be used with a warningcontroller 100 in accordance with an embodiment of the present inventionto alert other drivers that an airbag has deployed in the car carryingthe warning system. It will be understood that the airbag system as wellas the following safety systems are only exemplary, and many othersafety systems are available to those skilled in the art to accomplishsubstantially the same results. As shown in FIG. 2, a front-passengerairbag 21 and a driver airbag 22 are deployed from the dashboard area 23of a vehicle. Also included is seatbelt tightener 24, which is used torestrain the occupant when the airbags deploy and sensor 1, which isused to detect that the vehicle is in a hazardous situation. Once sensor1 detects an external pressure exerted on the vehicle, a signal is sentfrom sensor 1 to ECU 10. ECU evaluates the information supplied bysensor 1 and determines whether to deploy airbags 21 and 22. If ECU 10determines that the airbags require deployment, ECU 10 generates asignal to activate the airbags. From the signal sent to activate theairbags, detecting circuit 5 determines, (via an electrical pulse or theabsence of an electrical pulse, for example), that the airbag(s) hasbeen deployed and communicates this information to warning controller100.

Upon vehicle collision, a pyrotechnic gas generator inflates (not shown)airbags 21 and 22 in a sudden, explosive process designed to ensurecomplete inflation prior to occupant contact. The airbags then respondto occupant contact with partial deflation in a response patterncalculated to combine "gentle" force absorption with physiologicallyacceptable surface pressure and decelerative forces for the occupant.This prevents, or at least greatly reduces, the probability of severityof head and chest injuries to the passenger and/or driver.

Separate airbags for the driver and front seat passenger protect againsthead and front injuries stemming from impact about less than 60 km/hagainst a solid obstacle. Airbags 21 and 22 also protect occupants whoare not wearing seatbelts, and are therefore of particular benefit inareas or regions where seatbelt use is not mandatory.

The gas generator inflates the full-sized driver airbags 22 withnitrogen (N₂) (volume approximately 50 to 60 liters) in 30 to 35 ms,while roughly 50 ms are required to fill the full-sized frontalpassenger airbag 21 where the volume is approximately 100 to 140 litersinstalled in the glove compartment area.

The seatbelt tightener 24 compensates for belt slack and the film-reeleffect by retracting (tightening the belts) to further enhance theprotection afforded by automatic seatbelts. Seatbelt tightener 24 alsoincludes buckle tightener 25. Buckle tightener 25 pulls the seatbeltbuckle rearward to simultaneously tighten the shoulder and lap belts.Buckle tightener 25 combines improved restraint with enhanced protectionagainst "submarining" (in which occupants slide forward beneath the lapbelts). A prerequisite for optimum protection is that the occupants'forward movement away from their seats remain minimal as they deceleratealong with the vehicle. This is achieved by triggering seatbelttightener 24 immediately upon initial impact to ensure that effectiverestraint starts as soon as possible. The maximum forward displacementwith tightened seatbelts is approximately 1 cm and the duration ofmechanical tensioning process is approximately 5 ms to a maximum of 12ms. Although seatbelt tightner 24 is used to further enhance the safetyof the occupants, the system for detecting airbag deployment can beactivated without the use of seatbelt tightner 24.

Of decisive importance to the safety of passengers is to trigger theprocess of releasing/inflating airbags at precisely the right instant.The occupants contact the airbag at the instant in which it is fullyinflated and just starting to deflate. Maximum forward displacement onthe driver's side is usually defined at 12.5 cm (the "5 inches rules")with airbag deflation times of approximately 100 ms. The entire impactand energy absorption process is therefore completed withinapproximately 150 ms. Moreover, as soon as this process has beentriggered, information about the airbag's deployment is communicated towarning controller 100. Warning controller 100 then sends a signal towarning indicator 200 which activates a light or horn or other warningsignal or device to alert other drivers of a hazardous condition.Generally, the warning signal can be adjusted to be detected at adistance of up to 1 mile and can be adjusted to be detected from the airor the road. Moreover, the warning system can be adjusted to distinguishbetween conventional vehicle audible or lighting systems. For example,strobe lights or other high-intensity lights can be used.

System For Detecting Rollover Protection System Deployment

A rollover protection system is a vehicular occupant protective systemdesigned to protect a vehicular occupant in the event that the vehicleoverturns. Many modern day sports cars and convertibles, particularly ofthe two-seat configuration, have a rollover bar that extends across thepassenger compartment just behind the seat structure for safety reasons.In vehicles with demand-deployment rollover bars and rear headrestraints an electronic triggering unit (rollover sensor) providessubstantially instantaneous protection in response to incipient vehicleroll by triggering a powerful solenoid to release a pre-tensionedactivation spring. Therefore, rollover bars protect occupants fromsevere injury when the vehicle overturns.

Referring now to FIG. 3, a convertible vehicle 31 is shown with arollover protection system. A roll bar 33 is pivotally mounted in thecenter of the vehicle. The roll bar 33 has a generally inverted U-shapedconfiguration with side leg portions 32 and 34 extending downward fromthe elongated upper or top portions thereof to a pivotal mountingassembly 35 which includes a main support bar 36.

The main support bar 36 is mounted in a suitable manner such as by abracket or the like at each end thereof, securing the support bar 36directly to a side wall panel in the interior of the vehicle's body.Because vehicle roll can be characterized by deviations from thehorizontal plane in any direction--both linear and lateral--the rolloversensors are able to monitor an extended range of vehicle attitudes.

Referring to FIG. 3, rollover sensor 2 is coupled to mounting assembly35. Mounting assembly 35 communicates with rollover sensor 2 to informthe sensor of the position of the vehicle. If the mounting assemblycommunicates to rollover sensor 2 a value that exceeds or falls below apredetermined value for describing the position of the vehicle, rolloversensor communicates this information to ECU 20. ECU 20 then determineswhether to activate the rollover protection system. Once ECU 20determines that the rollover protection system should be activated,detecting circuit 6 detects activation of the protection system andimmediately forwards the information to warning controller 100. Warningcontroller 100 then sends a signal to warning indictor 200 which alertsother drivers of a hazardous condition. Rollover sensor 2 is alsocoupled to an external sensor (not shown) to determine the position ofthe car with respect to the ground and the speedometer (not shown) todetermine the speed of the vehicle.

Data employed by rollover sensor 2 to detect an impending roll, includesthe vehicle's acceleration and tilt angles as well as extension rates atthe rear suspension and loss of contact between the vehicle and the roadsurface. Separate acceleration sensors for the longitudinal and lateralplanes monitor vehicular acceleration in all directions. A microcomputerlocated in ECU 20 squares and sums the sensor signals before comparingthe resulting acceleration data with the programmed activation thresholdof roughly 5 g (where g is the acceleration of a freely falling object).A tilt switch evaluates the vehicle tilt as a second triggeringcriterion. The system also deploys the rollover bar 36 if vehicleinclination reaches more than 27 degrees and at least one of the tworear-axle switches has opened to generate a signal indicating rear-wheelrebound. The microcomputer and an analog hardware path furnish redundantverification of the second triggering condition in order to increaseoperating safety.

As well as the triggering functions, the rollover sensor 2 also carriesout self-diagnosis, in which the external actuators, the rear-suspensionswitches, electrical system voltage and the warning lamp are diagnosed.It has a non-volatile memory, a fault clock and a serial diagnosticinterface. The system responds to activation conditions by releasing thecentral locking system. Other lateral roll-detection systems employ tiltsensors to determine the vehicle's angular inclination (where the rollangle is greater than 52 degrees and the pitch angle is greater than orequal to 72 degrees). Another alternative is to use a gravity sensordesigned to respond to the loss of road contact characteristic ofincipient rollover by closing a spring-loaded Reed contact. As soon asrollover sensor 2 detects that the vehicle exceeds a predeterminedvehicular angular inclination, this information is communicated towarning controller 100. Warning controller 100 then sends a signal towarning indicator 200 which activates a light or horn or other warningsignal or device to alert other drivers of a hazardous condition.

A System For Detecting Obstacles With Ultrasonic Sensors:

The obstacle detector system of the invention functions to determine thedistance of a vehicle from an obstacle and to warn other vehicles if adangerous condition is detected. The term "obstacle" is used herein tomean a stationary or moving object within the path of the sensor, suchas for example, vehicles, pedestrians, etc. The system includes at leastone ultrasonic sensor and an evaluation circuit to determine thedistance of the vehicle from an obstacle. Referring to FIG. 4, a blockdiagram of a circuit arrangement for the obstacle detector system isshown. Ultrasonic sensor 41 transmits sound waves and measures thetransmitted time of an echo reflected from an obstacle. In thisarrangement, the measurement of the distance from the obstacle issufficiently precise during the approach to an obstacle as far as to aspecific minimum value. The ultrasonic sensor(s) can be located under oron the front and/or rear bumpers of the vehicle. In the alternative,ultrasonic sensors can be located in any area which is useful fordetecting the presence of an obstacle when the vehicle is traveling atvarious speeds and in various directions.

The block diagram of FIG. 4 illustrates ECU 30, which has amicroprocessor 45 with a program memory 46. Contained in the programmemory 46 is a control program used for measured value registration andevaluation. Also included in ECU 30 and functionally connected tomicroprocessor 45 is a system activation indicator 44. System activationindicator 44 may be for example, an output port which is used todetermine whether the system has been activated. The microprocessor 45is functionally connected to a display 47, on which the distance valuesare displayed so that the driver or passenger may detect the display.Microcomputer 45 is also connected on the input side to one or moreultrasonic sensors 3. The functions of microprocessor 45 includetriggering the abovementioned components and monitoring any defectsdiscovered in the system.

Sensors 3 are in the form of a housing such as an aluminum housingoptionally having selective damping, a piezoelectric wafer as a wavegenerator, and the electronic circuitry necessary for the generation ofultrasonic waves and evaluation of reflected, received waves. In analternative embodiment, sensors 3 may be already provided with the useof another system, such as for example, the ABS or the rolloverprotection system.

The obstacle detecting system can become activated only when theignition is switched on, and the transmission engaged. Operationgenerally starts with an initial self-test in which display 41 andsensors 3 are activated and checked for correct operation. Uponcompletion of the self-test, the system indicates correct functioningeither by means of a "ready" display or by indicating the distance to anobstacle. If a fault is detected (for instance a cable breaks), awarning tone or light or other signal is switched on for about 3seconds. The driver is informed of the system status either optically oraudibly or both, and has the option of switching off the system by meansof a switch (not shown) if circumstances demand. This can be the casefor instance in "stop-and-go" traffic at speeds below 15 km/h.

While driving, the sensors are triggered approximately every 50 ms,preferably every 40 ms and most preferably every 25 ms and generate anultrasonic pulse of about 1-5 ms, preferably about 1 ms. The sensors 3then switch to "listen" so that they can receive reflected waves. Thedistance to an obstacle from which the waves are reflected is calculatedby processing the transmitted time taken for the waves to travel fromthe transmitting sensor to the receiving sensor. The shortest distancein each case from the obstacle to the bumper is optionally indicated tothe driver on display 47.

The system may be programmed to detect obstacles which are apredetermined distance away from the vehicle at a given speed or thesystem can be automatically set to detect obstacles at a predetermineddistance without driver intervention. For example the system may beprogrammed to detect an obstacle at 15 feet at 25 mph or 40 feet at 65mph. Sensor(s) 3 are used to determine the position of the vehicle inrespect to a detected obstacle. The sensors communicate this informationto microprocessor 45 which alerts the obstacle system that an obstacleis within the predetermined or programmed range. Once microprocessor 45determines that an obstacle is too close to the vehicle and the vehiclehas not decelerated, microprocessor 45 communicates with display 47 toalert the driver of a potentially hazardous situation. Detecting circuit7 detects that the obstacle system has been activated and forwards thisinformation to warning controller 100. The warning controller 100signals warning indicator 200 to warn others of a potential hazard.System For Detecting (ABS) Antilock Braking System Deployment:

Antilock braking systems (ABS) are closed loop control devices withinthe braking system which prevent wheel lock up during braking and, as aresult, retain the vehicle's steerability and stability. The maincomponents of ABS are a hydraulic module, wheel-speed sensors, and amicroprocessor for signal processing and control of actuators in thehydraulic modular.

Upon initial braking, brake pressure is increased; the brake slipincreases and at a maximum point on an adhesion/slip curve, the brakeslip reaches a limit between a stable and unstable range. From thispoint on, any further increase in the brake pressure or braking torquedoes not result in a further increase in the braking force. In thestable range, the brake slip is largely the result of a deformationslip. The brake slip increasingly tends toward skidding in the unstablerange.

Referring now to FIG. 5, one example of an ABS control system that canbe used with the present invention is shown. The ABS control systemgenerally includes a solenoid-valve unit 51, master cylinder 52, a wheelbrake cylinder 53, an electronic control unit 40 including amicroprocessor 56 and a wheel speed sensor 4. Wheel-speed sensor 4monitors the motion of the wheel 58. If one wheel shows signs oflocking, there is a sharp rise in peripheral wheel deceleration and inwheel slip. If these exceed defined critical conditions, the ECU 40sends a command to solenoid-valve unit 51 to stop or to reduce thebuildup of wheel-bake pressure until the danger of lock up has passed.The brake pressure must then be built up again in order to ensure thatthe wheel is not under braked. During automatic brake control, it isconstantly necessary for the stability or instability of the wheelmotion to be detected, and the wheel must be kept in the slip range withmaximum braking force by a succession of pressure-buildup,pressure-reduction and pressure-holding phases. When the ABS system isactivated, ECU 40 forwards a signal to microprocessor 56 that automaticbraking control is being employed. Detecting circuit 8 detects thesignal sent to microprocessor 56 and alerts warning controller 100 thatthe ABS system has been activated. Warning controller 100 then notifieswarning indicator 200 that the vehicle may be experiencing a hazardouscondition. Warning indicator 200 is then activated.

Alternative Subsystems Deployable With Warning Control:

Another example of a subsystem that can be included (eitheralternatively or collectively) with the vehicular warning systeminclude, for example, is a vehicle dynamic system. Vehicle dynamics isdefined herein as the overall behavior of the entire system representedby "driver +vehicle +environment". As the first link in the chain, thedriver makes judgements on vehicle operating behavior based on the sumof various subjective impressions. Meanwhile, data on operatingbehavior, based on specific driving maneuvers executed without driverinput ("open-loop operation") provide an objective description of thevehicle's operating response. Since the driver's driving behavior cannotbe precisely defined, testing and/or warning systems of the presentinvention replace the driver input with a specific, objectivelyquantifiable interference factor. The resulting vehicular response isthen analyzed and an appropriate response made.

Standardized versions of the driving maneuvers in the list (performed ona dry road surface) below have already either been defined or are underconsideration; they serve as recognized standard procedures forvehicular evaluation:

Steady-state skidpad,

Transient response,

Braking during cornering,

Crosswind sensitivity,

Straight-running stability, and

Reaction to throttle change on skidpad.

To date, it has still not been possible to arrive at comprehensiveobjective definitions for the dynamic characteristics associated withclosed-loop operation, as adequate data on the precise controlcharacteristics of the human element are still unavailable.

The main criteria employed in evaluating vehicle dynamics are:

Steering-wheel angle,

Lateral acceleration,

Longitudinal acceleration and deceleration,

Yaw speed,

Float and roll angles.

Additional data are employed to verify and confirm the previouslyderived information on specific points of vehicle performance:

Linear and lateral velocity,

Steering angles at front and rear wheels,

Slip angles at all wheels,

Camber and pitch angles,

Steering-wheel force.

A detecting circuit can be employed to detect and monitor the operationof any of these features alone or in combination. The detecting circuitcan be connected to warning controller 100 to indicate activation of oneor more of the above-mentioned safety devices.

There has thus been shown and described a novel system for automaticallywarning others of hazardous conditions experienced by the driver of avehicle in which the system is installed. Many changes, modifications,variations and other uses and applications of the subject invention,will however, become apparent to those skilled in the art afterconsidering this specification and the accompanying drawings whichdisclose the preferred embodiments thereof. All such changes,modifications, variations and other uses and applications which do notdepart from the spirit and scope of the invention are deemed to becovered by the invention which is limited only by the following claims.

What is claimed is:
 1. A vehicular hazard warning system comprising:(a)at least one sensor being triggered by an event and producing a signal;(b) at least one controller for receiving said signal and determiningwhether to activate a vehicle safety device; (c) at least one detectingcircuit which detects activation of a vehicle safety device by saidcontroller; and (d) at least one hazard warning indicator which isdetectable externally to a vehicle containing the warning system, saidhazard warning indicator being activated in response to the detectedactivation of said safety device.
 2. The vehicular warning systemaccording to claim 1, wherein said at least one warning indicator is alight or auditory signal.
 3. The vehicular warning system according toclaim 2, wherein said at least one warning indicator is a horn.
 4. Thevehicular warning system according to claim 2, wherein said at least onewarning indicator is a high intensity light.
 5. The vehicular warningsystem according to claim 1 comprising a plurality of said detectioncircuits.
 6. The vehicular warning system according to claim 1, whereinsaid at least one detecting circuit is an antilock brake deploymentdetecting circuit.
 7. The vehicular warning system according to claim 1,wherein said at least one detecting circuit is an airbag deploymentdetecting circuit.
 8. The vehicular warning system according to claim 1,wherein said at least one detecting circuit is a rollover protectionactivation detecting circuit.
 9. The vehicular warning system accordingto claim 1, wherein said at least one detecting circuit is an obstacledetector detecting circuit.
 10. A vehicle having a vehicular hazardwarning system comprising:(a) at least one sensor being triggered by anevent and producing a signal; (b) at least one controller for receivingsaid signal and determining whether to activate a vehicle safety device;(c) at least one detecting circuit which detects activation of a vehiclesafety device by said controller; and (d) at least one hazard warningindicator which is detectable externally to a vehicle containing thewarning system, said hazard warning indicator being activated inresponse to the detected activation of said safety device.
 11. A methodfor activating a vehicular hazard warning system comprising thesteps:(a) detecting a hazardous condition; (b) communicating thedetected hazardous condition to a control unit; (c) determining whetherthe hazardous condition exceeds a predetermined threshold; (d)activating at least one safety device if potentially hazardous conditionexceeds the predetermined threshold; (e) monitoring said control unitfor activation of said vehicle safety device (f) detecting activation ofsaid safety device; and (g) activating said warning hazard system inresponse to the detected activation of said safety device.
 12. Themethod for activating a hazard warning system according to claim 11,wherein the step of activating said warning hazard system comprisesilluminating a light or sounding an auditory signal or both.
 13. Themethod for activating a hazard warning system according to claim 11,wherein the step of activating said warning hazard system comprisessounding a horn.
 14. The method for activating a hazard warning systemaccording to claim 11, wherein the step of activating said warninghazard system comprises illuminating a light.
 15. The method foractivating a hazard warning system according to claim 14, wherein thelight is a high intensity light.
 16. The method for activating a hazardwarning system ac cording to claim 11, wherein the step of detecting theactivation of a safety device comprises detecting activation of anantilock braking system .
 17. The method for activating a hazard warningsystem according to claim 11, wherein the step of detecting theactivation of a safety device comprises detecting activation deploymentof an airbag or airbags.
 18. The method for activating a hazard warningsystem according to claim 11, wherein the step of detecting theactivation of a safety device comprises detecting activation of arollover protection system.
 19. The method for activating a hazardwarning system according to claim 11, wherein the step of detecting theactivation of a safety device comprises detecting the presence of anobstacle.
 20. The method for activating a hazard warning systemaccording to claim 11, further comprising the step of reset ting saidhazard warning system.
 21. A vehicular hazard warning systemcomprising:(a) at least one sensor being triggered by detecting ahazardous driving condition and producing a signal; (b) at least onecontroller for receiving said signal; (c) at least one detecting circuitwhich receives an indication from said controller of a hazardous drivingcondition; (d) at least one hazard warning indicator which is detectableexternally to a vehicle containing the warning system, said hazardwarning indicator being activated in response to an indication from saidat least one detecting circuit.